ESP8266 Community Forum

- Wed Apr 06, 2022 7:23 pm #94204 Semi-new to coding.
Equipment: ESP8266 board, CD74HC4067 16-Channel Multiplexer

Code Platform: micropython using Thonny on RPi transmitting over USB cable.

Project Goal: 16 individual photo-resistors to trigger individual LEDs or Relays.

Code:
Opening Line...

Code: Select allfrom machine import Pin, ADC
from time import sleep_ms

s0 = Pin(16, Pin.OUT) # assigns s0 on multiplexer to D0 pin on ESP8266
s1 = Pin(5, Pin.OUT)  # D1
s2 = Pin(4, Pin.OUT)  # D2
s3 = Pin(2, Pin.OUT)  # D4
SIG_pin = ADC(0)  # assigns SIG on multiplexer to A0 pin on ESP8266

to test the code, I ran the super simple...

Code: Select allval = Sig_pin.read()
print(val)

and I get a value which reflects an output... i'm not sure from which of the (16) channels. If i comment 3 out of 4 of the s# pins, I get a change in value as expected... but again, I'm not sure which channel from the active pin.

I have thought about it and I can create a binary directory to use for the channels.

Code: Select allmux = [{0b0000},{0b0001},{0b0010},{0b0011}],[{0b0100},{0b0101},{0b0110},{0b0111}],[{0b1000},{0b1001},{0b1010},{0b1011}],[{0b1100},{0b1101},{0b1110},{0b1111}]

In arduino, i could use ```digitalWrite(pin,channel)``` to call for a specific channel, but how can I do this in python?
and then how can I get the ```Sig_pin``` to read that specific pin & channel?

- Sat Apr 09, 2022 3:35 am #94228 Hi, I think you can take a look at this tutorial: https://out-of-cheese-error.netlify.app ... 8266-to-16